ComboBox.SelectedItem Property

When you set the SelectedItem property to an object, the ComboBox attempts to make that object the currently selected one in the list. If the object is found in the list, it is displayed in the edit portion of the ComboBox and the SelectedIndex property is set to the corresponding index. If the object does not exist in the list, the SelectedIndex property is left at its current value.

Note
The ComboBox class searches for the specified object by using the IndexOf method. This method uses the Equals method to determine equality.

The following code example shows the usage of the SelectedIndex and the SelectedItem properties. The example is part of a complete code example in the ComboBox class overview.

private void showSelectedButton_Click(object sender, System.EventArgs e) {
    int selectedIndex = comboBox1.SelectedIndex;
    Object selectedItem = comboBox1.SelectedItem;

    MessageBox.Show("Selected Item Text: " + selectedItem.ToString() + "\n" +
                    "Index: " + selectedIndex.ToString());
}

.NET Framework

.NET Framework Client Profile

Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Reference